In 1939
Finnish Naval Forces [Merivoimat] was composed
of Coastal Defence [Rannikkopuolustus] and Coastal
Fleet [Rannikkolaivasto]. Coastal Defence
led directly by Naval Forces Staff was composed
of Coastal Artillery [Rannikkotykistö] and Coastal
Infantry [Rannikkojalkaväki]. Strong Coastal
Artillery was the backbone of the Finnish coastal
defence and a relatively weak Coastal Fleet [Rannikkolaivasto]
was intended to a mobile coastal artillery force with its
new coastal armoured ships especially in the direction of
demilitarized Åland Islands. Although weak in number
coastal troops were a remarkable force with their heavy
and super heavy long-range coastal guns..
.

Coastal Artillery Units

In 1939 the
largest coastal defence unit in Finland was a regional Coastal Sector (Rannikkolohko [or
Lohko], Lo.). The
whole Finnish sea coastline (about 1.600 km) was divided
into ten coastal sectors. These independent coastal
defence units were composed of the various number of Subsectors
(Alalohko, ALo.) equal to an artillery battalion.

The defended
area of a subsector was divided into Guard Regions
(Vartioalue) supervised by coastal troops. On the most
threatened and heavily defended areas along the Gulf of
Finland coastline and passages were secured with coastal
batteries which were usually in fortified bases called as
Fort (Linnake, Ln. also Lke).

Fort had
typically one or more Coastal Batteries (Rannikkopatteri,
RPtri) with one to six guns in open or armoured positions.
The oldest coastal batteries were in open line positions
but modernized and new batteries were decentralized and
camouflaged and in some cases there were also decoy
batteries. Most new batteries had firing sectors of 360
degrees instead of the earlier limited one. Armoured
batteries had usually armour shields open at rear but
some of the heaviest 305 mm (12") batteries were in
armoured single or twin gun turrets.

Coastal
sectors and subsectors had usually subordinated infantry
and naval units. Areas less suitable for a large scale
invasion were only patrolled by infantry or motor boats
of the Coast Guard [Merivartiolaitos] and local
units of Civil Guard [Suojeluskunta].

In western
Finland coastal sectors were under the command of two
regional headquarters which commanded and conducted also
naval units, naval traffic and subordinated naval air
units (see from the Finnish Air Force 1939 - 1940 page).
Aircraft operated in naval reconnaissance role detecting
Soviet war ships, especially surfaced submarines.

Notes:
- # There are two different dates mentioned in
TALHI but this one is more likely. Another date
is 17.12.1939.
- * Captain (Capt.) [Kommodori] = Naval rank
equal to Colonel.
- ..Commander (Cmd. senior) [Komentaja]
= Naval rank equal to Lieutenant Colonel.....(There is also Cmd. junior
[Komentajakapteeni] rank which is equal to Major.)

There were no
specialized coastal infantry units in Finland during the
Winter War. Separate machinegun and bicycle companies as
well as separate infantry battalions and one bicycle
battalion were although subordinated to Naval Forces
Staff for the coastal defence. These units were
usually improperly equipped and armed with obsolete or
non-standard weapons. Personnel consisted mainly of older
age classes with the average age of over 30 years and officers
were usually reservists.

These units
were clearly rated as secondary troops but despite of
that most of them were later transferred to the front
where they fought as well as other Finnish units. All
infantry units subordinated to and formed by the Naval
Forces are described on the page Naval Infantry Units 1939 - 1940..
.

Other Coastal Defence Detachments
and Groups

Åland
Islands

Åland
Islands Group (Ahvenanmaan Ryhmä, AR) was
formed in Turku in November 1939 for the quick occupation
and defence of the militarily neutralized Åland Islands
[Ahvenanmaa]. Group was under the command of Finnish Supreme
HQ. It was composed of two parts: Detachment H
(Osasto H, Os.H) and Artillery Battalion A (Patteristo
A, Psto A, also A-psto) which was a coastal artillery
unit and became the bulk of the coastal artillery troops
of Åland Islands Sector (Ahvenanmaan lohko, ALo.)
which was a former Coast Guard's Åland
Islands District re-named on 2.12.1939.

Already at
the end of November 1939 it was obvious that Hanko
Peninsula was even more threatened by the Soviets than
Åland Islands. Åland Islands Group was
therefore suspended and halved into a new Detachment
H (Osasto H) which was moved to Hanko Peninsula and Defence of Åland Islands (Ahvenanmaan puolustus, AP) of
which troops were moved to Åland Islands. This new
command HQ had only a few infantry units under its
command in addition to Åland Islands Sector
which was responsible of the coastal defence.They were part of the Naval
Defence of South-West Finland (L-SMe.P).
.

Hanko
Sector (Ha.Lo.) and all its infantry units were
subordinated temporarily to Os.H. The task of
the detachment was to repel enemy invasion attempts at
Hanko and Lappohja region. When no invasion seemed to
happen against the southern coast of Finland Os.H
was suspended on 6.12.1939 and the major part of its HQ
was transferred to north from Lake Ladoga where it became
Detachment Talvela (Osasto Talvela, Os.T).

On 8.12.1939 Infantry
Regiment 22 (originally from the 8th Division)
was moved away and attached to 6th Division
which was in reserve of Supreme HQ on western
Karelian Isthmus. On 1.1.1940 6.D was re-named
as 3rd Division and JR 22 became Infantry
Regiment 9 (JR 9). 6th/3rd Division had
earlier given its own Infantry Regiment 16 (JR
16) to Detachment Talvela..

Bay
of Viborg and Eastern Gulf of Finland

Naval
Forces Staff was at first responsible of the defence
of Bay of Viborg [Viipurinlahti]. Since February 1940
the initially weak coastal defence was hastily reinforced
by forming new artillery units. Temporary artillery units at Bay of Viborg were equipped with
guns without recoil system.

On 18.2.1940 Karelian
Isthmus Army (Kannaksen Armeija, Kan.A) took the
command of all coastal troops on this area. A new
regional HQ called Viborg Coastal Sector (Viipurin
rannikkolohko, Vi.RL also VRLo.) was formed on 28.2.1940.
It was re-named already on 1.3. as Coastal
Group (Rannikkoryhmä, Ran.R also RR) (Commander
Maj.Gen. M. Wallenius, 3.3.40- Lt.Gen. L.
Oesch). It had the following units under its command:
Viborg Sector (until 7.3. only), 4th
Division, Group Berg (Ryhmä B) (with Infantry
Regiment 9, Separate Battalions 19, 20, 22, 24
and a few battalions of the Field Supplement Brigade)
and Detachment Varko (Os.V) (with Separate
Battalion 7 and Bicycle Battalion 5).

Hamina
Group(Haminan Ryhmä, HR) (Commander
Maj.Gen. E. Hanell) was formed on 7.3.1940 west
from the Coastal Group (RR) between Vilajoki and
the city of Kotka. Kotka Sector (KLo.), Combat
Detachment Paalu (Tst.Os.P) and Viborg Sector
(VLo.) were now subordinated to HR which was
directly under the command of Supreme HQ. Viborg
Sector and Combat Detachment Paalu were
merged together on 11.3. but command arrangements were
still under way when the Winter War ended on 13.3.1940..
.